Preform extended finish for processing light weight ecologically beneficial bottles

ABSTRACT

Disclosed are preforms which incorporate improvements in the region of the neck and upper segment of the body to allow the production of lightweight containers, such as bottles suitable for containing water or other beverages. In accordance with certain embodiments, the improvements include a thinner neck finish area than conventional bottles, where the thinner area is extended into the upper segment of the body portion below the support ring. Reducing the thickness in these areas of the bottle allows for less resin to be used in forming the preform and bottle.

PRIORITY

This application is a continuation in part of, and claims the benefitof, U.S. patent application Ser. No. 15/013,141, entitled “PreformExtended Finish For Processing Light Weight Ecologically BeneficialBottles,” filed Feb. 2, 2016, which is a continuation in part of, andclaims the benefit of, U.S. patent application Ser. No. 14/590,705,filed Jan. 6, 2015, which is a continuation of, and claims the benefitof, U.S. patent application Ser. No. 13/295,699, filed on Nov. 14, 2011,which claims benefit to U.S. Provisional Patent Application Ser. No.61/413,167, filed Nov. 12, 2010. Each of the aforementioned applicationsis incorporated by reference in its entirety into this application.

FIELD

The field of the present disclosure generally relates to plastic bottlesand preforms. More particularly, the field of the present disclosurerelates to plastic performs and bottles blown from such preforms thatare suitable for containing beverages and utilize less resin such thatthey are lighter in weight than conventional bottles.

BACKGROUND

Plastic containers have been used as a replacement for glass or metalcontainers in the packaging of beverages for several decades. The mostcommon plastic used in making beverage containers today is polyethyleneterephthalate (PET). Containers made of PET are transparent, thinwalled, and have the ability to maintain their shape by withstanding theforce exerted on the walls of the container by their contents. PETresins are also reasonably priced and easy to process. PET bottles aregenerally made by a process that includes the blow-molding of plasticpreforms which have been made by injection molding of the PET resin.

Advantages of plastic packaging include lighter weight and decreasedbreakage as compared to glass, and lower costs overall when taking bothproduction and transportation into account. Although plastic packagingis lighter in weight than glass, there is still great interest increating the lightest possible plastic packaging so as to maximize thecost savings in both transportation and manufacturing by making andusing containers that contain less plastic.

SUMMARY

A new approach which relies on a general change in preform design hasbeen invented, which significantly improves the ability to blowefficient, lightweight bottles. The design elegantly incorporatesfeatures for protecting critical dimensions of the bottle andstabilizing the production blowing process. These features may alsoutilize less resin while achieving suitable mechanical performanceresulting in a reduction in the use of petroleum products by theindustry.

In accordance with embodiments disclosed herein, there is provided aplastic preform suitable for forming a bottle, and a bottle or containermade from such a preform. The preform comprises a neck portion adaptedto engage a closure and including a support ring at its lowermost point,the neck portion having a first wall thickness, and an elongated bodyportion including a generally cylindrical wall portion and an end cap.In some embodiments, the upper segment of the body portion adjacent tothe support ring has a second wall thickness substantially similar tothe first wall thickness and less than a third wall thickness in a lowersegment of the body portion. Further embodiments may include one or moreof the following features: the second wall thickness is about 25% toabout 40% of the third wall thickness; the second wall thickness isabout 25% to about 30% of the third wall thickness; the second wallthickness is about 0.7 mm to about 0.8 mm; an axial length of the uppersegment is about 25% or more of an axial length of the neck portion;and/or an axial length of the upper segment is about 25% to about 35% ofan axial length of the neck portion. In other embodiments, the secondwall thickness is thicker or thinner than the first wall thickness by0.1 mm, 0.2 mm, 0.3 mm, or 0.4 mm. Containers or bottles made from suchpreforms are also disclosed herein.

In accordance with embodiments disclosed herein, there is provided aplastic preform, comprising a neck portion often including a supportring, wherein the neck portion has a first wall thickness, and a bodyportion including an elongated cylindrical wall having upper, middle andlower segments, wherein the middle segment has a second wall thicknessand the lower segment of the body portion includes an end cap. In someembodiments, the upper segment of the body portion has a wall thicknesssubstantially similar to the first wall thickness and less than thesecond wall thickness and/or the axial length of the upper segment isabout 25% or more of the axial length of the neck portion. Furtherembodiments may include one or more of the following features: the uppersegment wall thickness is about 25% to about 40% of the second wallthickness; the upper segment wall thickness is about 25% to about 30% ofthe second wall thickness; the upper segment wall thickness is about 0.7mm to about 0.8 mm; and/or an axial length of the upper segment is about25% to about 35% of an axial length of the neck portion. In otherembodiments, the upper segment wall thickness is thicker or thinner thanthe first wall thickness by 0.1 mm, 0.2 mm, 0.3 mm, or 0.4 mm.Containers or bottles made from such preforms are also disclosed herein.

In an exemplary embodiment, a preform suitable for being blow-molded toform a container comprises a neck portion comprising an opening to aninterior of the preform; a tapered portion comprising a smoothtransition from a diameter of the neck portion to a smaller diameter ofa cylindrical portion comprising an elongate member that extends to anend cap; and a finish disposed on the neck portion and configured tothreadably receive a cap.

In another exemplary embodiment, the tapered portion comprises a wallthickness that smoothly transitions from a wall thickness of the neckportion to a relatively greater wall thickness of the cylindricalportion, the wall thickness of the tapered portion and the wallthickness of the cylindrical portion being suitable for beingblow-molded into a predetermined shape and size of the container.

In another exemplary embodiment, the finish comprises one or morethreads configured to rotatably engage with threads disposed within thecap. In another exemplary embodiment, the one or more threads eachextends along a section of the circumference of the neck portion. Inanother exemplary embodiment, the one or more threads are spaceduniformly around the circumference of the neck portion. In anotherexemplary embodiment, adjacent of the one or more threads share anintervening valley configured to allow passage of a thread disposed inthe cap.

In another exemplary embodiment, the neck portion comprises a pluralityof internal columns disposed within the opening and configured to imparta degree of structural integrity to the neck portion and reduce anamount of material comprising the preform. In another exemplaryembodiment, the plurality of internal columns comprises three internalcolumns that are positioned at substantially 120-degree intervals aroundthe circumference of the neck portion.

In another exemplary embodiment, the neck portion comprises one or moreexterior columns configured to maintain a necessary degree of structuralintegrity of the preform and reduce the amount of material comprisingthe preform. In another exemplary embodiment, the one or more exteriorcolumns are disposed uniformly around the perimeter of the neck portion,each of the exterior columns comprising a vertically aligned thickerregion of the neck portion. In another exemplary embodiment, the one ormore exterior columns are positioned in locations around the perimeterof the neck portion that coincide with the locations of internal columnswithin the opening of the neck portion. In another exemplary embodiment,the one or more exterior columns are positioned at specific intervalsbetween the locations of internal columns within the opening of the neckportion. In another exemplary embodiment, adjacent exterior and interiorcolumns are separated by 60-degree intervals around the circumference ofthe neck portion.

In another exemplary embodiment, the neck portion comprises a beveldisposed at a beginning of the opening and configured to enter intosliding contact with a sealing flange of the cap, the bevel beingconfigured to compress the sealing flange to a predetermined degree,thereby forming a tight seal suitable to retain pressurized contentswithin the container.

In an exemplary embodiment, a preform suitable for being blow-molded toform a container comprises a neck portion comprising an opening to aninterior of the preform; a body portion comprising a tapered portionthat smoothly transitions from the neck portion to a cylindrical portionand an end cap, the body portion comprising a wall thickness suitablefor being blow-molded into a desired shape and size of the container; afinish disposed on the neck portion and configured to threadably receivea cap; a plurality of internal columns disposed within the opening; oneor more exterior columns disposed around the perimeter of the neckportion; and a bevel disposed at a beginning of the opening andconfigured to receive a sealing flange of the cap.

In another exemplary embodiment, the plurality of internal columns andthe one or more exterior columns are configured to maintain a degree ofstructural integrity of the neck portion and reduce the amount ofmaterial required to form the preform. In another exemplary embodiment,the tapered portion comprises a smooth transition from a diameter and awall thickness of the neck portion to a relatively smaller diameter anda greater wall thickness of the cylindrical portion.

In another exemplary embodiment, the finish comprises at least threethreads configured to rotatably engage with threads disposed within thecap, and wherein an intervening valley is disposed between adjacent ofthe at least three threads and configured to allow passage of a threaddisposed in the cap. In another exemplary embodiment, each of the atleast three threads extends along a section of the circumference of theneck portion. In another exemplary embodiment, the section comprisessubstantially 144-degrees of the circumference. In another exemplaryembodiment, the at least three threads are spaced uniformly around thecircumference of the neck portion.

In an exemplary embodiment, a PET preform for forming a heat-setcontainer comprises: a cylindrical portion configured to be blow-moldedinto the heat-set container; and a neck portion that couples a finishwith the cylindrical portion.

In another exemplary embodiment, the neck portion tapers from the finishto a diameter of the cylindrical portion. In another exemplaryembodiment, a wall thickness of the neck portion smoothly transitions toa predetermined wall thickness of the cylindrical portion. In anotherexemplary embodiment, the predetermined wall thickness is suitable forbeing blow-molded into the heat-set container. In another exemplaryembodiment, the predetermined wall thickness is configured for beingblow-molded into a heat-set container suitable for containingpressurized contents. In another exemplary embodiment, the predeterminedwall thickness is selected such that the heat-set container may beconfigured to withstand nitrogen hot-filling with pressurized contents.

In another exemplary embodiment, the finish includes an opening to aninterior of the cylindrical portion. In another exemplary embodiment,the finish is configured to accommodate a relatively large headspacesuitable for nitrogen hot-filling the heat-set container withpressurized contents. In another exemplary embodiment, the finishincludes at least one thread configured to rotatably engage with threadsdisposed in a cap. In another exemplary embodiment, the opening includesa bevel configured to receive a sealing flange disposed in a cap so asto form a seal suitable to retain pressurized contents within theheat-set container. In another exemplary embodiment, the at least onethread extends along a section of the circumference of the finish. Inanother exemplary embodiment, the at last one thread includes threethreads that are uniformly spaced around the circumference of thefinish.

In an exemplary embodiment, a PET preform for forming a heat-setcontainer comprises: a cylindrical portion configured to be blow-moldedinto the heat-set container; a neck portion coupled with the cylindricalportion; and a finish disposed on the neck portion and including anopening to an interior of the cylindrical portion.

In another exemplary embodiment, the cylindrical portion includes a wallthickness that is suitable for being blow-molded into a heat-setcontainer capable of withstanding nitrogen hot-filling of the containerwith pressurized contents.

In another exemplary embodiment, the neck portion tapers from a diameterof the finish to a diameter of the cylindrical portion. In anotherexemplary embodiment, a wall thickness of the neck portion transitionsto a predetermined wall thickness of the cylindrical portion. In anotherexemplary embodiment, the predetermined wall thickness is suitable forblow-molding at least the cylindrical portion into a heat-set containercapable of withstanding nitrogen hot-filling the heat-set container withpressurized contents.

In another exemplary embodiment, the finish is configured to receive acontainer cap so as to retain pressurized contents within the heat-setcontainer. In another exemplary embodiment, at least one thread iscircumferentially disposed on the finish and configured to rotatablyengage with threads disposed in the container cap. In another exemplaryembodiment, the finish is configured to accommodate a headspace suitablefor nitrogen hot-filling the heat-set container with pressurizedcontents.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings refer to embodiments of the present disclosure in which:

FIG. 1 illustrates a side plan view of an exemplary embodiment of apreform suitable for being blow-molded to form a bottle, according tothe present disclosure;

FIG. 2A illustrates a cross-sectional view of an exemplary preformwithout an extended lightweight finish;

FIG. 2B illustrates a cross-sectional view of another exemplary preformwithout an extended lightweight finish;

FIG. 2C illustrates a cross-sectional view of an exemplary embodiment ofa preform in accordance with the present disclosure;

FIG. 3 illustrates a cross-sectional view of a preform in the cavity ofa blow-molding apparatus of the type that may be used to make a bottleor container, according to the present disclosure;

FIG. 4 illustrates a side plan view of an exemplary embodiment of abottle or container that has been blow-molded by way of the apparatusillustrated in FIG. 3, according to the present disclosure;

FIG. 5A illustrates a micro-CT slice of a neck and upper body of anexemplary preform as illustrated in FIG. 2A;

FIG. 5B illustrates a micro-CT slice of the neck and upper body of anexemplary embodiment of a preform as is illustrated in FIG. 2C, inaccordance with the present disclosure;

FIG. 6 illustrates a superimposition of micro-CT slices of an exemplarypreform as illustrated in FIG. 5B and a bottle blown therefrom;

FIG. 7A illustrates a side plan view of an exemplary embodiment of apreform suitable for being blow-molded to form a bottle in accordancewith the present disclosure;

FIG. 7B illustrates a cross-sectional view of the preform illustrated inFIG. 7A, taken along a line 7B-7B, according to the present disclosure;

FIG. 7C illustrates a cross-sectional view of the preform illustrated inFIG. 7A, taken along a line 7C-7C in accordance with the presentdisclosure;

FIG. 8A illustrates a side plan view of an exemplary embodiment of aneck portion suitable for being incorporated into a preform, such asillustrated in FIG. 7A, in accordance with the present disclosure;

FIG. 8B illustrates a cross-sectional view of the exemplary neck portionillustrated in FIG. 8A, taken along a line 8B-8B, according to thepresent disclosure;

FIG. 8C illustrates a close up, detail view of a portion of thecross-sectional view illustrated in FIG. 8B, in accordance with thepresent disclosure;

FIG. 9A illustrates a cross-sectional view of the exemplary neck portionillustrated in FIG. 8A, taken along a line 9A-9A, in accordance with thepresent disclosure;

FIG. 9B illustrates a close up, detail view of a cross-sectional profileof threads illustrated in FIG. 9A, in accordance with the presentdisclosure;

FIG. 9C illustrates a close up, detail view of a cross-sectional profileof a neck ring illustrated in FIG. 9A, according to the presentdisclosure; and

FIG. 9D illustrates a close up, detail view of a cross-sectional profileof a support ring illustrated in FIG. 9A, in accordance with the presentdisclosure.

While the present disclosure is subject to various modifications andalternative forms, specific embodiments thereof have been shown by wayof example in the drawings and will herein be described in detail. Theinvention should be understood to not be limited to the particular formsdisclosed, but on the contrary, the intention is to cover allmodifications, equivalents, and alternatives falling within the spiritand scope of the present disclosure.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the present disclosure. Itwill be apparent, however, to one of ordinary skill in the art that theinvention disclosed herein may be practiced without these specificdetails. In other instances, specific numeric references such as “firstpreform,” may be made. However, the specific numeric reference shouldnot be interpreted as a literal sequential order but rather interpretedthat the “first preform” is different than a “second preform.” Thus, thespecific details set forth are merely exemplary. The specific detailsmay be varied from and still be contemplated to be within the spirit andscope of the present disclosure. The term “coupled” is defined asmeaning connected either directly to the component or indirectly to thecomponent through another component. Further, as used herein, the terms“about,” “approximately,” or “substantially” for any numerical values orranges indicate a suitable dimensional tolerance that allows the part orcollection of components to function for its intended purpose asdescribed herein.

Disclosed herein are articles, including preforms and containers, whichutilize less plastic in their construction while maintaining the ease ofprocessing and excellent structural properties associated with currentcommercial designs.

FIG. 1 illustrates a side plan view of an exemplary embodiment of apreform 30 suitable for being blow-molded to form a bottle, according tothe present disclosure. The preform is preferably made of materialapproved for contact with food and beverages such as virgin PET and canbe of any of a wide variety of shapes and sizes. The preform shown inFIG. 1 is of the type which will form a 12-16 oz. beverage bottle, butas will be understood by those skilled in the art, other preformconfigurations may be used depending upon the desired configuration,characteristics and use of the final article. The preform 30 may be madeby injection molding methods including those that are well known in theart.

FIG. 2A illustrates a cross-sectional view of an exemplary preform 30.The preform 30 has a neck portion 32 and a body portion 34, formedmonolithically (i.e., as a single, or unitary, structure).Advantageously, the monolithic arrangement of the preform, whenblow-molded into a bottle, provides greater dimensional stability andimproved physical properties in comparison to a preform constructed ofseparate neck and body portions, which are bonded together.

The neck portion 32 begins at an opening 36 to an interior of thepreform 30 and extends to and includes a support ring 38. The neckportion 32 is further characterized by the presence of a structure forengaging a closure. In the illustrated embodiment, the structureincludes threads 40, which provide a means to fasten a cap to the bottleproduced from the preform 30. The illustrated preform has a shorteroverall neck area than most conventional preforms, which shorter neckarea may also be thinner than in conventional preforms. The thickness ofthe neck area 52A is measured at the very top or between the threads orany other protruding structures.

The body portion 34 comprises an elongated structure extending down fromthe neck portion 32 and culminating in an end cap 42. In someembodiments the body portion 34 may be generally cylindrical, and theend cap 42 may be conical or frustoconical and may also behemispherical, and the very terminus of the end cap may be flattened orrounded. The preform wall thickness 44 through most of the body portion34 will depend upon the overall size of the preform 30 and the wallthickness and overall size of the resulting container. The preform wallthickness between 48 A and 50 A is slightly thinner than the wallthickness throughout the straight portion of the body portion, both ofwhich are thicker than at 46 A immediately below the support ring 38. Aslight taper often below 0.01 mm may also be found from 50 A to 44 tohelp with release of the injected preform from the core duringprocessing.

FIG. 2B illustrates a cross-section of another embodiment of a prior artpreform 30. The preform 30 has a neck portion 32 and a body portion 34.The neck portion 32 of the preform is of an axial length as may be foundin conventional preforms. Although the thickness of the upper segment orportion of the body portion 46B is of a similar thickness as the neckportion 52B, it is also substantially similar thickness or the samethickness as the remainder of the body portion of the preform (e.g. 44B,50B). In contrast to the preform 30 illustrated in FIG. 2B, the preformillustrated in FIG. 2C is substantially thicker in the middle segment(e.g. 44C) of the body and in the end cap 42 than in the upper segment(e.g. 46C) of the body portion, which is of a similar thickness or samethickness as the neck portion 52C. In other embodiments, the uppersegment of the body portion (e.g. 46C) may be thinner than the neckportion 52C.

In contrast to the preform illustrated in FIG. 2A, the preform 30illustrated in FIG. 2C has a reduced thickness in the upper portion ofthe body portion 34 of the preform below the support ring 38, in thatpoint 46C is substantially thinner than the corresponding location 46Ain the prior art preform, 48C is of similar thickness to 46C which ismuch thinner than 48A of the prior art preform, and the thicknessincreases from point 48C to 50C, at which point the body portion 34transitions into the straight portion of the preform having thethickness 44C. Preforms and containers blown from such preforms havingsuch a thinned area at the uppermost portion of the body portion aresometimes referred to herein as having an “extended finish.” A furtherillustration of this difference, in accordance with one embodiment, canbe seen in FIG. 5B and FIG. 6. Further, the preform 30 illustrated inFIG. 2C also has a shorter overall neck area than most conventionalpreforms. As will be appreciated, the shorter neck area may also bethinner than in conventional preforms.

As compared to the prior art preform in FIG. 2A, the thickness at 46C isabout 20-50% of the thickness at 46A, the thickness at 48C is about20-60% of the thickness at 48A, and the thickness at 50C is about80-100% of the thickness at 50A. In one embodiment, the thicknesses of46C and 48C differ by less than about 20%, including less than about10%, or they are substantially the same thickness. As an example, for apreform used to form an 8 oz. bottle, the thickness at 46C is about 0.7mm, the thickness at 48C is about 0.8, and the thickness at 50C is about2 mm. By means of comparison, for the prior art preform used to form an8 oz. bottle, the thickness at 46A is about 1.5 mm the thickness at 48Ais about 2 mm, and the thickness at 50A is about 2.5 mm. As anotherexample, for a preform used to form a 16.9 oz. bottle, the thickness at46C is about 0.7 mm, the thickness at 48C is about 1 mm, and thethickness at 50C is about 2.4 mm, compared to about 1.2 mm at 46A, about1.8 mm at 48A, and about 2.4 mm at 50A in a prior art preform. Asanother example, for a preform used to form a 33.8 oz. bottle, thethickness at 46C is about 0.75 mm, the thickness at 48C is about 1 mm,and the thickness at 50C is about 2.6 mm, compared to about 1.5 mm at46A, about 1.9 mm at 48A, and about 2.7 mm at 50A in a prior artpreform. The total weight of a preform used to form an 8 oz. bottleaccording to FIG. 2C is about 7 grams as compared to about 12.5 gramsfor a preform according to FIG. 2A. The total weight of a preform usedto form a 16.9 oz. bottle according to FIG. 2C is about 8.5 grams ascompared to about 9.2 grams for a preform according to FIG. 2A. Thetotal weight of a preform used to form a 33.8 oz. bottle according toFIG. 2C is about 18.3 grams as compared to about 26 grams for a preformaccording to FIG. 2A. Using the information provided herein, one skilledin the art can prepare other sizes of preforms that have similarcharacteristics to those described herein. Also, the dimensions in otheruseful embodiments of preforms may vary from the above-stated dimensionsby between substantially 0.1 mm and substantially 1 mm, inclusive.

In accordance with certain embodiments, the upper segment of the bodyportion of the preform, which is adjacent to the support ring, has athickness that is substantially similar to the thickness 52C of the neckportion 32. In some such embodiments, the thicknesses of the uppersegment and the neck portion 32 may differ by +/−0 mm, 0.1 mm, 0.2 mm,0.3 mm, or 0.4 mm. In some such embodiments, the thicknesses of theupper segment and the neck may differ by up to 10%, up to 20%, or up to30%. Accordingly, the thickness of the upper segment of the body portionof the preform may be substantially the same thickness, or it may beeither thicker or thinner than the neck portion 52C. In accordance withother embodiments, the thickness of the upper segment of the bodyportion 34 of the preform is less than that of a middle or lower segmentof the body portion. In some such embodiments, the wall thickness of theupper section is about 10% to about 40% of the thickness of the lowerand/or middle section of the body, including about 15% to about 40%,about 15% to about 30%, about 25% to about 35%, about 20% to about 35%,about 20% to about 30%, including about 12%, about 13%, about 17%, about19%, about 22%, about 24%, about 27%, about 29%, about 31%, and about33%, including ranges bordered and including the foregoing values. Insome such embodiments, the wall thickness of the upper segment of thebody is about 0.3 mm to about 0.9 mm, including about 0.3 mm to about0.5 mm, about 0.4 mm to about 0.7 mm, about 0.5 mm to about 0.9 mm,about 0.7 mm to about 0.8 mm, including about 0.35 mm, about 0.45 mm,about 0.55 mm, about 0.65 mm, about 0.75 mm, and about 0.85 mm,including ranges bordered and including the foregoing values. Inaccordance with other embodiments, the axial length of the upper segmentmeasures about 20% or more, including about 25% or more of the axiallength of the neck portion, including about 20% to about 30%, about 20%to about 35%, about 25% to about 30%, and about 25% to about 35% of theaxial length of the neck portion. Preforms may include one or more orall of the features described above.

After a preform, such as that depicted in FIGS. 2A, 2B and 2C, isprepared by injection molding, the preform is subjected to a stretchblow-molding process. Referring to FIG. 3, in this process a preform 50is placed in a mold 80 having a cavity corresponding to a desiredcontainer shape. The preform 50 is then heated and expanded bystretching such as by a stretch rod inserted into the center of thepreform to push it to the end of the mold and by air forced into theinterior of the preform 50 to fill the cavity within the mold 80,creating a container 82. The blow-molding operation normally isrestricted to the body portion 34 of the preform with the neck portion32, including the support ring 38, retaining the original configurationas in the preform.

When performing the stretch blow-molding process to create thecontainer, preforms are conventionally loaded onto a spindle whichengages the inner wall of the neck portion of the preform andfacilitates transporting the preform into and through the stretchblow-molding machinery. Because of the extended neck finish inaccordance with embodiments described herein, it may be beneficial tohave the spindle extend into the inner wall of the preform into theregion of the upper segment of the body portion, beyond the neckportion. In some embodiments, the spindle loads into the preform thefull extent of the extended neck finish. This may be accomplished byadjusting the depth to which the spindle loads and/or by changing thespindle to have sufficient length to extend the greater distance. Theextended spindle loading depth helps to maintain the dimensions of theextended neck finish, especially in those embodiments where the extendedneck finish is relatively thin such that the dimensional stability ofthe lower part of the extended neck finish and/or the lower part of theupper segment of the body portion would otherwise be at risk due toexposure to heating elements and/or elevated temperatures in otherportions of the body during the stretch blow-molding process.

FIG. 4 illustrates a side plan view of an exemplary embodiment of acontainer 82 that may be made by way of blow-molding the preform 50 ofFIG. 3, or the preforms 30 illustrated in FIGS. 2A, 2B and 2C. Thecontainer 82 has a neck portion 32 and a body portion 34 correspondingto the neck and body portions of the preforms 30 illustrated in FIGS.2A, 2B and 2C. The neck portion 32 is further characterized by thepresence of threads 40 or other closure engagement means that provides away to fasten a cap onto the container 82.

In preforms having neck finishes that are lighter in weight and portionsimmediately below the finish (uppermost portion of the body), such asthose described herein, the lighter weight portions are more susceptibleto damage or softening from the heat supplied to the remainder of thepreform during blow-molding. Aggressive cooling of the finish was seenas a way to enable light weighting. Since not all machines coolidentically or as effectively, it was observed that to properly blow thebottle, the finish would go through distortion. A short term solution toprevent distorting the finish was to limit heating of the preform belowthe support ring 38. This left plastic from the preform in the neck ofthe bottle. This is referred to as a “ring” in the neck. Whileunattractive and inefficient from a resin use perspective, such adecision allowed the light weight preform to continue to produceacceptable bottles.

Thus, a concept was conceived where the material normally placed in thepreform to be stretched from directly below the support ring was removedand replaced with a wall thickness at the desired dimensions of thefinished product. The distance of this bottle “neck” was set by thebottle design, but the new extended finish concept allows for someheating and stretching. By definition the design change also providesfor a transition from fully blown bottle to rigidly retained threadsacross this zone. An extended finish is especially useful in smallerfinishes that are substantially shorter from the support ring to the topof the finish as compared to prior finishes that have considerabledistance (up to 10 mm) from the threads to the base of the support ring.Such shorter finishes may also be thinner. This new design was alsodiscouraged because having a thin area upstream of a thicker threadedarea in an injection mold would be difficult, if not impossible, to moldproperly since it would likely prevent resin from completely filling theneck finish under usual injection pressures. Thus injection limitationshave historically limited this approach rather than mechanicalperformance. Accordingly, in some embodiments, during the injectionmolding process, the closing of the neck ring can be slightly delayed toallow filling of the small spaces before clamping it down to mold atleast the neck and finish. Minimal experimentation is needed todetermine the correct timing and amount of polymer melt to ensurecomplete filling of the neck and finish while minimizing flashing.

In addition to providing lighter weight preforms and bottles, theextended finish preforms disclosed herein, which may incorporate otherlightweighting features described herein such as a shorter and/orthinner neck and/or thinner walls in the body portion, can also have theadvantage of being produced using a lower cycle time in molding. Lowercycle time increases the number of preforms that can be made by a singlepiece of equipment in a day and can lower the total energy needed toproduce a single preform, resulting in additional cost savings to themanufacturer.

It was also generally thought that a thicker support ring and largeramounts of plastic near that region (above in the finish and below atthe uppermost portion of the body) was needed to absorb heat and preventit from transferring into the finish. This has also been shown by thepresent applicant to be incorrect. It has been found that the thick ringof plastic provides heat storage and serves as a heat source duringlater bottle handling and processing steps. Thinning the region belowthe support ring, under this new perspective, provides resistance toheat travelling up to the finish in that this area can rapidly cool sothat it is not a latent heat source during later operations. Since, incertain embodiments, this region does not need to be stretched duringblow-molding, it does not need to be heated and the blow-moldingprocedure and apparatus may be adjusted such that the uppermost portionor upper segment of the preform/container body (in the area of theextended finish) is not heated, or heated very little as compared to thebulk of the body of the preform, as part the blow-molding process. Thischange is easy to accommodate in modem equipment and makes theproduction process easier and more stable. For example, the position ofthe cooling rail or shims may be adjusted to provide greater protectionfrom heat for the extended finish, the intensity of the heatingelement(s) may be adjusted, and/or the position of the heatingelement(s) may be adjusted. It should be noted that preforms having anextended finish may be blow-molded in conventional processes thatactively heat the lower portion of the extended finish (i.e. theuppermost portion of the body), but such processes are generally lesseffective in creating consistently stable bottles during production.

The applicant has discovered that when the preform of FIG. 2A is blownto form a bottle in a process that protects the extended finish fromheating during blow-molding as described above, the thickness at 46A and48A changes very little, with essentially all of the wall portion of thebottle being formed from the stretching of the wall around 50A andbelow. This is shown in FIG. 6 which presents a superimposition ofcross-sections of a preform having an extended finish and a bottle blowntherefrom. Accordingly, the wall thickness at the lower segment of theneck portion of the preform, including at 46C and 48C, is lessened asdescribed hereinabove to reduce the amount of material needed to formthe preform while still maintaining the necessary degree of structuralintegrity to allow for ease in blow-molding to form a container that hassufficient mechanical strength to withstand the forces exerted on itduring formation, filling, transportation and use.

In accordance with some embodiments herein, the width of the supportring may be increased as compared to that in a standard shorter finish.Given that a 0.6 mm width to the support ring (as in a standard shorterfinish) provides forces upon a finger that are considered to be withinthe pain threshold for a finger, increasing the width may providegreater comfort for the consumer. Accordingly, a width of at least about1 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2 mm, 2.2 mm, 2.4 mm, 2.6 mm orgreater would provide greater comfort to the consumer when opening theclosure. Alternatively or concomitantly, changes may be made to the capincluding by increasing the apparent cap diameter such as by providingribs on the tamper ring that are of greater height than the remainingcap. Other reasons to widen the ring include conveyor handling, heatsink properties of the ring, better feel when opening the container,greater resistance to damage during processing and transport. It shouldbe noted that increasing the width of the support ring is counter tolightweighting, such that it should be balanced with otherconsiderations when designing a preform and container.

In some embodiments, in which it is desired for the container to beheat-set, it is preferred that the containers be blow-molded inaccordance with processes generally known for heat set blow-molding,including, but not limited to, those which involve orienting and heatingin the mold, and those which involve steps of blowing, relaxing andreblowing. The mold 80 can quickly cool the container during thisprocess, especially with high heat transfer material absorbing heat fromthe container at a high rate.

In some embodiments, the blow-mold may be used to produce crystallineneck finishes. For example, the neck portion of the blow-mold and thebody portion of the blow-mold can selectively control the temperature ofthe preform/container to achieve a desired amount of crystallization.Thus, the neck portion of the preform/container can be heated andgradually reduced in temperature to produce a desired amount ofcrystalline material.

In some embodiments, a PET preform may be configured for forming aheat-set container, such as by way of blow-molding the preform inaccordance with processes generally known for heat-set blow-molding. ThePET preform may be comprised of a cylindrical portion configured to beblow-molded into the heat-set container capable of withstanding beingnitrogen hot-filled with pressurized contents. In some embodiments, aneck portion may configured to couple a finish with the cylindricalportion.

The finish generally includes an opening to an interior of thecylindrical portion. In some embodiments, the finish may be configuredto accommodate a relatively large headspace suitable for nitrogenhot-filling the heat-set container with pressurized contents. The finishmay include at least one thread that is circumferentially disposed onthe finish and configured to rotatably engage with threads in acontainer cap so as to retain pressurized contents within the heat-setcontainer.

In some embodiments, the neck portion of the PET preform may be taperedfrom a diameter of the finish to a diameter of the cylindrical portion.A wall thickness of the neck portion may be configured to transition toa predetermined wall thickness of the cylindrical portion that issuitable for being blow-molded into the heat-set container. In someembodiments, the predetermined wall thickness may be suitable forblow-molding at least the cylindrical portion into a heat-set containercapable of withstanding nitrogen hot-filling with pressurized contents.

In some embodiments for preforms in which the neck finish is formedprimarily of PET, the preform may be heated to a temperature ofpreferably 80° C. to 120° C., with higher temperatures being preferredfor the heat-set embodiments, and given a brief period of time toequilibrate. After equilibration, the preform may be stretched to alength approximating the length of the final container. Following thestretching, pressurized air, such as chilled food grade air, may beforced into the preform which acts to expand the walls of the preform tofit the mold in which it rests, thus creating the container. Fluid maybe circulated through the mold so as to rapidly cool the containercontacting the interior surface. The temperature of the chilled air forstretching the preform and the temperature of the fluid cooling the moldmay be selected based on the desired container finish, production time,and the like.

FIGS. 7A through 7C illustrate an exemplary embodiment of a preform 90suitable for being blow-molded to form a bottle, such as the container82, in accordance with the present disclosure. Similar to the preforms30, 50, the preform 90 comprises a neck portion 32 and a body portion 34that are monolithically formed. The neck portion 32 begins at an opening36 to an interior of the preform 90 and extends to a tapered portion 92of the body portion 34. The tapered portion 92 comprises a smoothtransition from a diameter of the neck portion 32 to a relativelysmaller diameter of a cylindrical 94 portion of the preform 90. Thecylindrical portion 94 is a generally elongate member that extends to anend cap 42.

As best shown in FIG. 7B, a wall thickness of the cylindrical portion 94is substantially uniform throughout the cylindrical portion and the endcap 42. A wall thickness of the tapered portion 92, however, generallydecreases from the wall thickness of the cylindrical portion 94 to arelatively thinner wall thickness of the neck portion 32. As discussedherein, the wall thickness of the cylindrical portion 94 is relativelygreater than the wall thickness of the neck portion 32 so as to providea wall thickness at the desired dimensions of a finished product afterbeing blow-molded into the shape and size of a bottle, such as thecontainer 82.

As shown in FIGS. 7B and 7C, the neck portion 32 may be characterized bya plurality of longitudinally oriented internal columns 96 within theopening 36. In the illustrated embodiment, the plurality of internalcolumns 96 comprises three internal columns that are equally spacedaround the circumference of the neck portion 32. Thus, as shown in FIG.7C, adjacent internal columns 96 are positioned at substantially120-degree intervals around the circumference of the neck portion 32. Aswill be appreciated, incorporating the plurality of internal columns 96into the neck portion 32 facilitates incorporating a wall thicknesswithin the neck portion that is relatively thinner than conventionalneck portions. Thus, the internal columns 96 facilitate a wall thicknesswithin the neck portion 32 of the preform 90 that reduces the amount ofmaterial needed to form the preform 90 while still maintaining thenecessary degree of structural integrity to allow for ease inblow-molding to form a container that has suitable mechanical strengthto withstand forces encountered during formation, filling,transportation, and use. It should be understood, however, that thenumber of internal columns 96 may be other than three, and that thespacing between adjacent internal columns 96 need not necessarily beuniform, nor limited to 120-degree intervals.

The neck portion 32 is further characterized by a presence of threads 40configured to rotatably engage with similar threads disposed within acap or other suitable closure so as to provide a way to seal contentswithin the container 82. In the embodiment illustrated in FIG. 7A, andas shown in greater detail in FIGS. 8A-9D, each of the threads 40generally extends along a section of the circumference of the neckportion 32 and approaches a neck ring 98. Thus, when the threads of acap are engaged with the threads 40, and the cap is rotated in aclockwise direction, the cap advances toward the support ring 38. Asbest shown in FIG. 8A, the threads 40 comprise three threads that eachbegins at a thread start 102 and extends along a substantially144-degree section of the neck portion 32. The thread start 102 isconfigured to guide the thread 40 into a space, or valley, betweenadjacent threads of the cap so as to threadably engage the cap with theneck portion 32, as described herein. Further, the threads 40 generallyare disposed adjacently to one another and are spaced uniformly aroundthe circumference of the neck portion 32. In the embodiment illustratedin FIG. 8A, the thread starts 102 of adjacent threads 40 are spaced atsubstantially 120-degree intervals around the perimeter of the neckportion 32. As will be appreciated, however, more or less than threethreads 40 may be incorporated into the neck portion 32 withoutdeviating beyond the scope of the present disclosure.

In some embodiments, one or more exterior columns 104 may beincorporated into the neck portion 32. Similar to the internal columns96, described above, the exterior columns 104 facilitate a wallthickness within the neck portion 32 of the preform 90 that reduces theamount of material needed to form the preform while still maintaining anecessary degree of structural integrity, as described herein. Thus, theexterior columns 104 may be incorporated into the neck portion so as topromote ease in blow-molding to form a container that has suitablemechanical strength to withstand forces encountered during formation,filling, transportation, and use

In the present embodiment, three exterior columns 104, each comprising avertically aligned thicker portion of the neck portion 32, are disposeduniformly around the perimeter of the neck portion, as best shown inFIGS. 8B and 8C. In some embodiments, however, other than three exteriorcolumns 104 may be disposed around the neck portion 32, such as, by wayof non-limiting example, two exterior columns disposed on opposite sidesof the neck portion 32, or four exterior columns disposed at 90-degreeintervals around the neck portion 32. Further, the spacing betweenadjacent exterior columns 104 need not be uniform around the perimeterof the neck portion, but rather the exterior columns may be disposed atvarious intervals around the neck portion.

Moreover, in some embodiments, the external columns 104 may bepositioned around the perimeter of the neck portion 32 so as to coincidewith the locations of the internal columns 96. In such embodiments,therefore, the internal columns 96 may be positioned directly beneaththe external columns 104. Alternatively, in some embodiments, theexternal columns 104 may be positioned at specific intervals betweenadjacent internal columns 96. For example, adjacent internal andexternal 96, 104 may be separated by 60-degree intervals. Further, theinternal and external columns 96, 104 need not necessarily be positionedat the same distance relative to the opening 36. In the embodimentillustrated in FIGS. 7A-9D, for example, the external columns 104 arepositioned above the neck ring 98, whereas the internal columns 96generally extend from the neck ring 98 into the tapered portion 92 ofthe preform 90, as best shown in FIG. 7B. It should be understood,therefore, that the internal and external columns 96, 104 may beincorporated onto the neck portion 32 in any configuration deemedsuitable without deviating beyond the spirit and scope of the presentdisclosure.

FIG. 9A illustrates a cross-sectional view of the neck portion 32, takenalong a line 9A-9A of FIG. 8A. As described above, the neck portion 32comprises a generally cylindrical member having an opening 36 suitableto provide access to an interior of the container 82. A bevel 106 isdisposed at the beginning of the opening 36. The bevel 106 is configuredto enter into sliding contact with a sealing flange of a suitable cap soas to prevent contents within the container 82 from leaking out of thecontainer. In some embodiments, the bevel 106 may compress the sealingflange to a predetermined degree, thereby forming a tight seal suitableto retain pressurized contents within the container 82.

FIGS. 9B through 9D illustrate detailed close up views of portions ofthe cross-sectional view of FIG. 9A. A cross-sectional profile of thethreads 40 is illustrated in FIG. 9B. The threads 40 generally extendoutward from the neck portion 32 such that a valley 108 is disposedbetween adjacent threads. The cross-sectional profile of the threads 40is configured such that the threads advantageously engage with similarthreads disposed within a suitable cap for sealing contents within thecontainer 82. As will be recognized by those skilled in the art, thevalley 108 is configured to allow passage of a thread disposed in thecap to pass between adjacent threads 40 during tightening of the caponto the neck portion 32, as described herein.

FIG. 9C illustrates a close up view of the cross-sectional profile ofthe neck ring 98. As shown in FIG. 9C, the neck ring 98 comprises arounded upper portion 112 and a substantially flat lower portion 116. Aswill be appreciated, the rounded upper portion 112 facilitates passing atamper-evident ring portion of the cap over the neck ring 98 duringassembly of the cap onto the container 82. The flat lower portion 116 isconfigured to retain the tamper-evident ring positioned below the neckring 98 during loosening of the cap. For example, when the cap isinitially installed onto the container 82 by a manufacturer, thetamper-evident ring easily passes over the neck ring 98 due to therounded upper portion 112. When an end-user later loosens the cap, theflat lower portion 116 retains the tamper-evident ring below the neckring 98, causing the tamper-evident ring to break loose from the cap.Thus, the flat lower portion 116 of the neck ring 98 and thetamper-evident ring of the cap cooperate to indicate to the end-userthat the cap has not been previously loosened after being installed bythe manufacturer.

FIG. 9D illustrates a close up view of the cross-sectional profile ofthe support ring 38. In the embodiment illustrated in FIG. 9D, thesupport ring 38 comprises a substantially flat lower surface 120. Aswill be recognized, the flat lower surface 120 of the support ring 38facilitates supporting the preform. 90 in the mold 80 during theblow-molding process described above and illustrated in FIG. 3.

The articles described herein may be made from any suitablethermoplastic material, such as polyesters including polyethyleneterephthalate (PET), polyolefins, including polypropylene andpolyethylene, polycarbonate, polyamides, including nylons (e.g. Nylon 6,Nylon 66, MXD6), polystyrenes, epoxies, acrylics, copolymers, blends,grafted polymers, and/or modified polymers (monomers or portion thereofhaving another group as a side group, e.g. olefin-modified polyesters).These materials may be used alone or in conjunction with each other.More specific material examples include, but are not limited to,ethylene vinyl alcohol copolymer (“EVOH”), ethylene vinyl acetate(“EVA”), ethylene acrylic acid (“EAA”), linear low density polyethylene(“LLDPE”), polyethylene 2,6- and 1,5-naphthalate (PEN), polyethyleneterephthalate glycol (PETG), poly(cyclohexylenedimethyleneterephthalate), polystryrene, cycloolefin, copolymer,poly-4-methylpentene-1, poly(methyl methacrylate), acrylonitrile,polyvinyl chloride, polyvinylidine chloride, styrene acrylonitrile,acrylonitrile-butadiene-styrene, polyacetal, polybutylene terephthalate,ionomer, polysulfone, polytetra-fluoroethylene, polytetramethylene1,2-dioxybenzoate and copolymers of ethylene terephthalate and ethyleneisophthalate. In certain embodiments preferred materials may be virgin,pre-consumer, post-consumer, regrind, recycled, and/or combinationsthereof.

In some embodiments polypropylene also refers to clarifiedpolypropylene. As used herein, the term “clarified polypropylene” is abroad term and is used in accordance with its ordinary meaning and mayinclude, without limitation, a polypropylene that includes nucleationinhibitors and/or clarifying additives. Clarified polypropylene is agenerally transparent material as compared to the homopolymer or blockcopolymer of polypropylene. The inclusion of nucleation inhibitors helpsprevent and/or reduce crystallinity, which contributes to the hazinessof polypropylene, within the polypropylene. Clarified polypropylene maybe purchased from various sources such as Dow Chemical Co.Alternatively, nucleation inhibitors may be added to polypropylene.

As used herein, “PET” includes, but is not limited to, modified PET aswell as PET blended with other materials. One example of a modified PETis IP A-modified PET, which refers to PET in which the IPA content ispreferably more than about 2% by weight, including about 2-10% IP A byweight, also including about 5-10% IP A by weight. In another modifiedPET, an additional comonomer, cylohexane dimethanol (CHDM) is added insignificant amounts (e.g. approximately 40% by weight or more) to thePET mixture during manufacture of the resin.

Additives may be included in articles herein to provide functionalproperties to the resulting containers. Such additives include thoseproviding enhanced gas barrier, UV protection, scuff resistance, impactresistance and/or chemical resistance. Preferred additives may beprepared by methods known to those of skill in the art. For example, theadditives may be mixed directly with a particular material, or they maybe dissolved/dispersed separately and then added to a particularmaterial. Additives are preferably present in an amount up to about 40%of the material, also including up to about 30%, 20%, 10%, 5%, 2% and 1%by weight of the material. In other embodiments, additives arepreferably present in an amount less than or equal to 1% by weight,preferred ranges of materials include, but are not limited to, about0.01% to about 1%, about 0.01% to about 0.1%, and about 0.1% to about 1%by weight.

Another possible additive is microparticulate clay or graphene basedmaterials. These materials comprise tiny, micron or sub-micron size(diameter), particles of materials which enhance the barrier and/ormechanical properties of a material by creating a more tortuous path formigrating gas molecules, e.g. oxygen or carbon dioxide, to take as theypermeate a material and/or providing added stiffness. In preferredembodiments nanoparticulate material is present in amounts ranging from0.05 to 1% by weight, including 0.1%, 0.5% by weight and rangesencompassing these amounts. One preferred microparticulate clay basedproduct is Cloisite® available from Southern Clay Products. In certainembodiments preferred nanoparticles comprise monmorillonite that may bemodified with a ternary or quaternary ammonium salt. In furtherembodiments, such particles comprise organoclays as described in U.S.Pat. No. 5,780,376, the entire disclosure of which is herebyincorporated by reference and forms part of the disclosure of thisapplication. Other suitable organic and inorganic microparticulate claybased or nano-sized products may also be used. Both man-made and naturalproducts are also suitable.

In some embodiments, the UV protection properties of the material may beenhanced by the addition of one or more additives. In a preferredembodiment, the UV protection material used provides UV protection up toabout 350 nm or less, preferably about 3 70 nm or less, more preferablyabout 400 nm or less. The UV protection material may be used as anadditive with layers providing additional functionality or appliedseparately as a single layer. Preferably additives providing enhanced UVprotection are present in the material from about 0.05 to 20% by weight,but also including about 0.1%, 0.5%, 1%, 2%, 3%, 5%, 10%, and 15% byweight, and ranges encompassing these amounts. Preferably the UVprotection material is added in a form that is compatible with the othermaterials. In some embodiments, a preferred UV protection materialcomprises a polymer grafted or modified with a UV absorber that is addedas a concentrate. Other preferred UV protection materials include, butare not limited to, benzotriazoles, phenothiazines, andazaphenothiazines. UV protection materials may be added during the meltphase process prior to use, e.g. prior to injection molding orextrusion. Suitable UV protection materials are available from Milliken,Ciba and Clariant.

While the invention has been described in terms of particular variationsand illustrative figures, those of ordinary skill in the art willrecognize that the invention is not limited to the variations or figuresdescribed. In addition, where methods and steps described above indicatecertain events occurring in certain order, those of ordinary skill inthe art will recognize that the ordering of certain steps may bemodified and that such modifications are in accordance with thevariations of the invention. Additionally, certain of the steps may beperformed concurrently in a parallel process when possible, as well asperformed sequentially as described above. To the extent there arevariations of the invention, which are within the spirit of thedisclosure or equivalent to the inventions found in the claims, it isthe intent that this patent will cover those variations as well.Therefore, the present disclosure is to be understood as not limited bythe specific embodiments described herein, but only by scope of theappended claims.

What is claimed is:
 1. A PET preform for forming a heat-set container,the preform comprising: a cylindrical portion configured to beblow-molded into the heat-set container; and a neck portion that couplesa finish with the cylindrical portion, a wall thickness of the neckportion transitions to a predetermined wall thickness of the cylindricalportion, wherein the predetermined wall thickness is suitable forblow-molding at least the cylindrical portion into a heat-set container;and wherein the finish is configured to accommodate a headspace fornitrogen hot-filling the heat-set container with pressurized contents.2. The preform of claim 1, wherein the predetermined wall thickness isconfigured for being blow-molded into a heat-set container suitable forcontaining pressurized contents.
 3. The preform of claim 1, wherein thepredetermined wall thickness is selected such that the heat-setcontainer may be configured to withstand nitrogen hot-filling withpressurized contents.
 4. The preform of claim 1, wherein the neckportion tapers from the finish to a diameter of the cylindrical portion.5. The preform of claim 4, wherein a wall thickness of the neck portionsmoothly transitions to a predetermined wall thickness of thecylindrical portion.
 6. The preform of claim 1, wherein the finishincludes an opening to an interior of the cylindrical portion.
 7. Thepreform of claim 6, wherein the finish includes at least one threadconfigured to rotatably engage with threads disposed in a cap.
 8. Thepreform of claim 7, wherein the opening includes a bevel configured toreceive a sealing flange disposed in a cap so as to form a seal suitableto retain pressurized contents within the heat-set container.
 9. Thepreform of claim 7, wherein the at least one thread extends along asection of the circumference of the finish.
 10. The preform of claim 7,wherein the at last one thread includes three threads that are uniformlyspaced around the circumference of the finish.
 11. A PET preform forforming a heat-set container, the preform comprising: a cylindricalportion configured to be blow-molded into the heat-set container; a neckportion coupled with the cylindrical portion, the neck portioncomprising a bevel disposed at a beginning of the opening and configuredto enter into sliding contact with a sealing flange of the cap, thebevel being configured to compress the sealing flange to a predetermineddegree, thereby forming a tight seal suitable to retain pressurizedcontents within the container; and a finish disposed on the neck portionand including an opening to an interior of the cylindrical portion-,wherein the neck portion tapers from a diameter of the finish to adiameter of the cylindrical portion.
 12. The preform of claim 11,wherein the cylindrical portion includes a wall thickness that issuitable for being blow-molded into a heat-set container capable ofwithstanding nitrogen hot-filling of the container with pressurizedcontents.
 13. The preform of claim 11, wherein a wall thickness of theneck portion transitions to a predetermined wall thickness of thecylindrical portion.
 14. The preform of claim 13, wherein thepredetermined wall thickness is suitable for blow-molding at least thecylindrical portion into a heat-set container capable of withstandingnitrogen hot-filling the heat-set container with pressurized contents.15. The preform of claim 11, wherein the finish is configured to receivea container cap so as to retain pressurized contents within the heat-setcontainer.
 16. The preform of claim 15, wherein at least one thread iscircumferentially disposed on the finish and configured to rotatablyengage with threads disposed in the container cap.
 17. The preform ofclaim 15, wherein the finish is configured to accommodate a headspacesuitable for nitrogen hot-filling the heat-set container withpressurized contents.